Traders Seek an Edge With High-Tech Snooping

CUSHING, Okla.—A helicopter lifted off recently from an airfield in this remote oil town, scudded low across the flat industrial landscape and trained a heat-sensitive camera at the huge storage tanks below.

Its mission: Gather intelligence for Wall Street.

The grainy, infrared reconnaissance images betrayed how much oil was in each tank. That gave Genscape Inc., the company that conducts the flights, a remarkably accurate...